The invention is directed to an electrical component having a base body that comprises a ceramic material and having at least two contact regions arranged in the base body to which terminal elements are secured. The component is enveloped with a protective layer containing organic constituents. The invention is also directed to a method for the manufacture of the electrical component.
German patent document DE 198 51 869 A1 discloses electrical components of the species initially cited that represent a hot-carrier thermistor temperature sensor composed of a disk-shaped ceramic material. In addition to leads attached to the material, the temperature sensor comprises an epoxy resin envelope that contains an auxiliary constituent with hydrophobic properties.
The known electrical component has the disadvantage that it is sensitive to moisture. Even though it has a hydrophobic envelope of epoxy resin that, for example, can be produced by immersion, outages can occur under the influence of moisture and/or water as a consequence of migration effects. Due to the adjacent voltage employed in the operation of the component, namely, there is a difference in potential between the two electrical poles of the ceramic element to which the leads are secured. When, under the use conditions in a humid environment, a closed water film forms between the electrodes, then a material transport starts (mediated by silver, tin and lead of the solder employed when soldering the leads on) from the anode to the cathode. Metallic films are formed that are capable of functioning similar to interconnects on the surface of the ceramic. The resistance of the sensor therefore decreases so greatly that a total outage of the hot-carrier thermistor temperature sensor can even occur under certain circumstance due to a short. Such hot-carrier thermistor temperature sensors can therefore only be provided for areas of employment wherein a moistening or, respectively, an influence of water at the temperature sensor does not occur.
In order to avoid the described problem, it is known from the Prior Art to provide the hot-carrier thermistor temperature sensor with a glass envelope. Given this design, however, no insulated leads can be utilized due to the high process temperatures. Moreover, there is a risk here that damage due to electro-chemical corrosion of the wires or migration via the glass member can occur given corresponding use conditions.